Vehicles

ABSTRACT

A VEHICLE WITH MULTISECTION BED WHICH IS EXTENDIBLE AND TILTABLE RELATIVE TO THE VEHICLE FRAME AND A FOOT ASSEMBLY PIVOTABLE DOWNWARDLY RELATIVE TO THE VEHICLE FRAME TO ELEVATE ONE END OF THE VEHICLE. FLUID-OPERATED MOTORS EFFECT THE TILTING OF THE BED AND THE MOVEMENT OF THE FOOT ASSEMBLY, AND A FLUID-OPERATED MOTOR-FLEXIBLE LINK ARRANGEMENT IS PROVIDED TO EXTEND AND RETRACT THE BED.

p ,19 C. w. PEWTHERS VEHICLES 6 Sheets-Sheet 1 Original Filed Nov. 29,1967 INVENTOR Charles W. Pew/hers P 1971 c. w. PEWTHERS 3,606,249

VEHICLES Original Filed Nov. 29, 1967 6 Sheets-Sheet 2 mvsmon Charles W.Pew/hers www w ATTORNEY 5 Sept. 20, 1911 |22 IZO IZZ 30' C. W. PEWTHERSVEHICLES iginal Filed Nov. 29, 1967 6 Sheets-Sheet 5 INVENTOR Char/es WPewf/vers ATTORNEYS Sept. 20, 1-971 c. w. PEWTHERS VEHICLES 6Sheets-Sheet 4 Original Filed Nov. 29, 1967 mvsmoa Char/es W HPWf/lQ/SSept. 20,1971 c;. w. PEWTHERS VEHICLES 6 Sheets-Sheet 5 Original FiledNov. 29, 1967 INVENTOR Charles W Pew/hers *fl%04 4 W@ ATTORNEYS p 1971c. w. PEWTHERS 3,606,249

VEHICLES Original Filed Nov. 29, 1967 6 Sheets-Sheet 6 RESERVOIRINVENTOR Charles W Pewrhers ATTORNE 5 United States Patent Ofice3,606,249 VEHICLES Charles W. Pewthers, 1015 Walton Drive, CollegeStation, Tex. 77840 Original application Nov. 29, 1967, Ser. No.686,575, now Patent No. 3,485,400, dated Dec. 23, 1969. Divided and thisapplication July 17, 1969, Ser. No. 862,560

Int. Cl. B60s 9/02 US. Cl. 254-86H 8 Claims ABSTRACT OF THE DISCLOSURE Avehicle with multisection bed which is extendible and tiltable relativeto the vehicle frame and a foot assembly pivotable downwardly relativeto the vehicle frame to elevate one end of the vehicle. Fluid-operatedmotors effect the tilting of the bed and the movement of the footassembly; and a fluid-operated motoreflexible link arrangement isprovided to extend and retract the bed.

This application is a division of my copending application Ser. No.686,575 filed Nov. 29, 1967 now Pat. No. 3,485,400.

The present invention relates to trucks and other loadcarrying vehiclesand, more specifically, to load-carrying vehicles with a novel,extendible, tiltable bed and a novel foot assembly for elevating one endof the vehicle when it is lowered.

It is a primary object of the present invention to provide novel,improved load-carrying vehicles which are more versatile and eflicientthan comparable load vehicles heretofore known.

The novel vehicles of the present invention by which the foregoing andother objects of the invention are attained include a bed slidablycarried by 'a sub-frame which in turn is pivotally fixed to the rear endof the vehicle frame. This permits the bed to be tilted upwardly and tobe extended relative to the vehicle frame for loading and unloading,dumping, and the like.

Coupled with this novel bed construction is a foot assembly which isalso pivotally fixed to the rear of the vehicle frame. The foot assemblycan be pivoted downwardly to elevate the rear of the vehicle. Thispermits the dock height of the bed to be adjusted to facilitate loadingand unloading and, also, permits below horizontal penetration of thebed. The foot assembly can also be lowered into engagement with thesurface on which the vehicle is standing during loading, unloading, andother operations to stabilize the vehicle.

In addition to the components just described the vehicles of the presentinvention have a novel combination of operating and control mechanismswhich permit the tilting, extension, and raising of the bed to beaccomplished independently. In the preferred embodiments of theinvention these mechanisms are of the fluid motor operated type. Thistype of operating mechanism has a number of advantages from theoperational standpoint as will become apparent hereinafter. In additionit has the further advantage that the fluid system can also be readilyemployed to power auxiliary devices such as winches, for example,thereby further increasing the versatility of vehicles in accord withthe principles of the present invention.

As suggested above and as will be apparent from the foregoing, oneimportant advantage of vehicles constructed in accord with theprinciples of the present invention is the high degree of versatilitythey possess. Other important advantages are that they are highlyefficient, have maximum strength and a long service life,

3,606,249 Patented Sept. 20, 1971 vehicles of the present invention areprovided. Accordingly, these prior art arrangements are not capable ofincreasing the versatility of the vehicles in which they are utilized toanywhere near the same extent as the foot assembly of my invention.

US. Pat. No. 3,074,574 to Prince is for vehicles having a bed which isextended and retracted by an arrangement similar in appearance to themechanism employed for this purpose in the present invention. However,as will become apparent from a closer comparison of the two mechanisms,that of the present invention is considerably simpler and less subjectto stress and other wear producing forces. Aside from this operatingmechanism there is little similarity between the vehicle described inthe foregoing patent and those of the present invention, the latterbeing much superior as far as versatility, simplicity, reliability, andother attributes are concerned.

Other load carrying vehicles with mechanisms similar to a limited exentto other of those preferably employed in the present invention such asthe bed elevating or tilting mechanism have also heretofore beenproposed. However, to date there has not been suggested anything evenremotely resembling vehicles with the specific novel features andcombinations thereof which provide those of the present invention withthe unique and important advantages described above.

From the foregoing it will be apparent that further important objects ofthe present invention reside in the provision of novel, improved loadcarrying vehicles which possess the following attributes and variouscombinations thereof: a high degree of efficiency, maximum strength,long service life, low operating costs, and low maintenance costs.

Another important but more specific object of the invention resides inthe provision of novel, improved load carrying vehicles having atiltable, extendible bed, a novel mechanism for elevating the rear endof the vehicle and thereby raising the bed to facilitate load andunloading, dumping, and other operations, and a novel controlarrangement which permits the tilting, extension, and raising of the bedto be effected independently.

Other important objects, further novel features, and additionaladvantages of the present invention will become fully apparent from theappended claims and as the ensuing detailed description and discussionproceeds in conjunction -with the accompanying drawing, in which:

FIG. 1 is a side view of a load-carrying vehicle constructed in accordwith the principles of and embodying the advantages of the presentinvention;

FIGS. 2-6 are views similar to FIG. 1 with the vehicle posited forvarious operations such as loading, unloading, dumping, and the like;

FIG. 7 is an exploded view of the vehicle frame, a sub frame which ispivotally fixed to the vehicle frame, and the vehicle bed, which isslidably carried by the sub-frame;

FIG. 8 is an end view of the vehicle bed and sub-frame;

FIG. 9 is a pictorial view of the vehicle bed, the subframe, and amechanism for extending and retracting the bed with respect to thesub-frame, the bed being shown in the retracted position;

FIG. is a view similar to FIG. 9, but with the bed extended relative tothe subframe;

FIG. 11 is a pictorial view of the bed extending and retractingmechanism;

FIG. 12 is a vertical section through the truck bed, showing a mechanismfor pivoting the sub-frame with respect to the vehicle frame and therebytilting the truck bed;

FIG. 13 is a side view of the components shown in FIG. '12 with a numberof details omitted for the sake of clarity;

FIG. 14 is a pictorial view of a novel foot assembly incorporated inload-carrying vehicles in accord with the present invention to raise therear end of the vehicle and thereby facilitate loading, unloading, andother operations',

FIG. 15 is a generally schematic side view of the foot assembly;

FIG. 16 is a pictorial view of the rear end of the loadcarrying vehicleframe and the components by which the foot assembly and the sub-frameare supported from the truck frame;

FIG. 17 is an exploded view of one of the foot assembly supportingcomponents and the pivot members by which the foot assembly andsub-frame are connected to the latter; and

FIG. 18 is a circuit diagram and schematic illustration of the hydraulicsystem preferably employed to operate the various mechanisms illustratedin FIGS. 1-17 and the controls therefor.

Referring now to the drawing, FIGS. 1-6 depict a novel load-carryingvehicle 20 constructed in accord with the principles of the presentinvention. Vehicle 20 includes a number of standard, conventionalcomponents such as a chassis or frame 22, a cab 24, and wheels 26 whichwill not be described further herein except as they relate to thepresent invention. Also incorporated in vehicle 20 are a sub-frame 28pivotally connected to vehicle frame 22 at the rear end of the vehicle,a bed 30 slidably carried by the sub-frame, a foot assembly 32 forelevating the rear end of the vehicle and for stabilizing it duringoperations such as loading, unloading and the like, and a novel systemincluding a control arrangement 34 for extending, retracting, andtilting bed 30 and for lowering foot assembly 32 to stabilize and/orraise the rear edn of vehicle 20.

Referring next to FIG. 7, the vehicle frame 22 on which sub-frame 28 andbed 30 are mounted will typically include a pair of longitudinallyextending structure members 36 joined into a rigid, unitary unit bycross members 38. The details of these members will vary from vehicle tovehicle, which is immaterial as far as the present invention isconcerned.

The sub-frame 28 carried by frame 22 is of similar construction,including two longitudinal structural members 40, which are six inch bysix inch tubes in one commercial embodiment of the invention. There arejoined into a rigid, unitary structure by a generally straight crossmember 42 at the rear end of the sub-frame and by generally V-shapedcross members 44 at intervals therealong. In the practice of the presentinvention the details of the sub-frame may be varied fromapplication-to-application, as desired, since they are not of criticalimport.

As indicated above, sub-frame 28 is pivotally fixed to vehicle frame 22at the rear end of vehicle 20. As is best shown in FIGS. 13 and 17, thisis accomplished by a pivot rod or member 46 which extends throughdepending ears 48 welded or otherwise attached to longitudinallyextending sub-frame structural members 40 and cooperating foot assemblysupporting components 50 at the rear end of longitudinal vehicle framestructural members 36 (see also FIGS. 7 and 16). Cotter keys or similarretainers 52 retain pivot rod 46 in place after the sub-frame isassembled to vehicle frame 22.

As shown in FIG. 17, each of the assemblies or components 50 includesplate-like support members 54 and 4 56 connected by a tubular spacer 58through which pivot member 46 extends. After these components areassembled, the assemblies are joined to frame members 36 by weldingplates 54 and 56 to the latter with the frame members extending intonotches 60 in the plates so that a high strength weld may be made.

Referring still to FIG. 7, the bed 30 carried by subframe 28 is ofgenerally conventional construction and includes a main section 61fabricated from longitudinally extending structural members 62 which arejoined by cross member 64 at the ends of the bed and cross members 66 atintervals therealong. Pockets 68 are preferably provided in structuralmembers 62 and 64 to accommodate a rack (not shown), thereby furtherenhancing the versatility of the vehicle.

In addition to the components just described, main section 61 of theillustrated exemplary bed 30 includes a floor 69, typical of two inch bysix inch tongue and groove yellow pine, surmounted by a floor plate 70of twelve gauge steel or the equivalent. These specifications may ofcourse be varied as desired.

In addition to main section 61, bed 30 preferably includes a cabprotector 71, which may be of generally the same construction as themain section, and a tail gate approach plate 72. Cab protector 7 1 ispivotally fixed to the front end of the main bed section by anappropriate hinge arrangement (shown in part in FIG. 7 and identified byreference character 73). Tailgate approach plate 72 is similarly hingedto the rear end of the main bed section and is preferably biased to thevertical position shown in FIG. 1 by an appropriate spring arrangement(not shown).

Releasable tie members 74 are provided to also maintain cab protector 71in a vertical position. By releasing these tie bars, however, cabprotector 71 can be lowered to the horizontal position shown in FIG. 2.to increase the length of the bed as will be explained in more detailhereinafter.

Referring now to FIGS. 7-10, bed 38 is slidably mounted on sub-frame 28by longitudinally extending, channel-shaped guides 75 welded orotherwise attached to the structural members of the bed. As shown inFIGS. 8-10, guides 75 embrace the outer, upper, and lower surfaces ofsub-frame longitudinal members 40, confining bed 30 to rectilinearmovement relative to the sub frame. Also, as shown in FIG. 8, phenolicor similar wear pads 76 are preferably interposed between sub-framestructural members 40 and guides 75 to minimize the frictiontherebetween as bed 30 is extended and retracted relative to thesub-frame.

The remaining major structural component of vehicle 20, aside from theoperating and control systems, is the foot assembly 32 best shown inFIGS. 14 and 15. Referring now to the latter figures, the foot assemblyincludes a pair of elongated, parallel, spaced apart structural members77 joined into a rigid, unitary structure by cross members 78. Alsoattached to members 77 is a transversely extending bar 80 carrying stopand tail lights 82 and '84.

Foot assembly 32 is pivotally fixed to the foot assembly supportcomponents 50 at the rear end of vehicle frame 22 by a pivot rod ormember 86, which extends through foot assembly structural members 77 andthe plate components 54 of the two assemblies. Cylindrical bushings 88are disposed between pivot rod 86 and support plates 54 to minimize thefriction therebetween.

In order to distribute the Weight of the vehicle and its load over asufficiently large area, shoes 90 are incorporated in foot assembly 32.As shown in FIG. 14, each of the shoes 90 includes a bearing plate 92 towhich plate-like supporting brackets 94- are fixed in parallel, spacedapart relationship. Shoes 90 are pivotally fixed to the structuralmembers 77 of the foot assemblies by pivot pins 96, which extend throughthe brackets 94 of each shoe and the associated structural member. Pins98 retain the pivot member in place after the shoe is assembled.

The versatility of load-carrying vehicle 20 resides in large part in thefact that bed 30 can be tilted and extended rearwardly with respect tothe vehicle frame and in that it can be raised by lowering foot assembly32 to elevate the rear end of the vehicle. Referring now to FIGS. 9-11,it will be remembered that bed 30 is extended and retracted by effectingrectilinear movement of the bed relative to sub-frame 28. The mechanismfor accomplishing this, identified generally in the foregoing figures byreference character 100, includes a fluid-operated motor 102, which maybe of the hydraulic type, and flexible links 104 and 106, which may befabricated of wire rope or the like. The cylinder 108 of the hydraulicmotor is fixed to the cross member 42 at the rear end of sub-frame 28and is also supported by the rearmost V- shaped cross member 44 with theV-configuration of the latter providing sufiicient room beneath bed 30to accommodate the motor cylinder.

Motor 102 is of conventional construction, including in addition tocylinder 108 a piston 1-10 to which a piston rod 112 is attached. Fixedto the free, exterior end of piston rod 112 is a U-shaped bracket 114'in which a double sheaved pulley 1 16 is rotatably supported by a shaft118. Flexible link 104 is trained around pulley 116 and connected, atone end, to a bracket 120 fixed to cross member 64 at the front end ofbed 30. The opposite end of link 104 is attached to the forwardmostcross member 44 of sub-frame 28.

Flexible link 106 is also trained around pulley 116 but in the oppositedirection of link 104. One end of link 106 is fixed by a suitablebracket (not shown) to bed 30 aft of its midpoint, and the other end ofthis link is fixed to the rearmost V-shaped cross member 44 of thesub-frame.

To extend bed 30 from the retracted position shown in FIG. 9 to theextended position shown in FIG. 10, operating fluid is admitted to theforward end of hydraulic motor cylinder 108, forcing piston 110, pistonrod 112, and pulley 116 toward the rear of vehicle 20. As pulley 116moves rearwardly, it pulls link 104 with it; and the link, in turn,pulls bed 30 rearwardly, moving the bed to the extended position of FIG.10.

In a typical application, the amount of travel thus provided will be onthe order of twelve feet. This distance can of course be varied asdesired.

The operation of mechanism 100 in retracting bed 30 (i.e., moving itfrom the extended position of FIG. to the position of FIG. 9) is similarto that just described Specifically, to retract the bed, the operatingfluid is admitted to the rear end of hydraulic motor cylinder 108,pushing piston 110, piston rod 112, and pulley 116 toward the front ofvehicle 20. As pulley 116 moves forwardly, it pushes flexible link 106toward the front of the vehicle, the link pulling bed 30 with it as itmoves forwardly.

Rearward movement of bed 30 is limited by the bottoming of piston 110 inthe rear end of hydraulic motor cylinder 108. Forward movement of thebed is limited by bed stops 122 (see FIG. 7) fixed to the longitudinalstructural members 40 of sub-frame 28. As the bed moves forwardly, thesestops are engaged by the forwardmost cross member 64 of bed 30,terminating its forward movement (see FIG. 8).

Referring now to FIGS. 17, 12, and 13, bed 30 is tilted to the positionsshown in FIGS. 3 and 6, for example, by pivoting sub-frame 28 upwardlywith respect to vehicle frame 22 about pivot member 46. The mech anismfor pivoting the bed includes two hydraulic motors 124 and 126 of thetype described previously supported in side-by-side relationship fromvehicle frame 22 by a saddle assembly .128. As best shown in FIGS. 7 and12, the latter component includes depending brackets 130 fixed to thelongitudinal structural members 36 of vehicle 6 frame 22 and atransversely extending support 132 connected between brackets 130 attheir lower ends. The cylinders 1134 of hydraulic motors 124 and 126 arepivotally fixed to support 132 by hinge assemblies 136.

Referring now to FIGS. 12 and 13, the free or exterior ends of thepiston rods 138 of hydraulic motors i124 and 126 are pivotally fixed toa cross member 44 of subframe 28 by hinge assemblies 139. Both these andthe hinge assemblies 136 may be of any appropriate construction.

To tilt bed 30 from the normal or lowered position shown in dotted linesin FIG. 13 to the elevated or raised position shown in full lines in thesame figure, operating fluid is admitted to the lower ends of cylinders134, driving the pistons 146 of the hydraulic motors upwardly togetherwith piston rods 138. As will be apparent from an inspection of FIG. 13,this rotates sub-frame 28 (and, accordingly, bed 30) upwardly in acounterclockwise di rection about pivot member 46. As the bed pivotsupwardly, the pivotal connections between the hydraulic motors andsupport 132 and between the motors and subframe 28 accommodate themovement of the motors from the position identified by referencecharacter 148 in FIG. 13 to that identified by reference character 150.

To return bed 30 from the tilted position'to its normal I horizontalposition, the process just described is reversed by admitting operatingfluid to the upper ends of hydraulic motor cylinders 134. This drivesthe pistons 146 and piston rods 138 downwardly, pivoting the sub-frameand bed clockwise to the dotted line, lowered position.

Referring now to FIGS. 14 and 15, the downward pivotal movement of footassembly 32 employed to elevate the rear end of vehicle 20* and therebyraise bed 30 is also effected hydraulically. More specifically, downwardand upward pivotal movement of foot assembly 32 is produced by afluid-operated motor .152 similar to those described previously. Thecylinder 154 of the motor is pivotally supported relative to vehicleframe 22 by the pivot member 46 about which sub-frame 28 rotates, whichextends through a cylindrical bracket 156 fixed to the upper end of thecylinder. At the opposite end of the motor, its piston rod 158 ispivotally attached to the center cross member 78 of the foot assembly bya pivot member 160. The latter extends through a cylindrical attachment162 fixed to the end of the piston rod and brackets 164 welded orotherwise fixed to the cross member.

To lower foot assembly 32 from the travel position shown in full linesin FIG. 15 to a position in which it elevates the rear end of vehicle 20from the surface 166 on which the vehicle is standing, operating fluidis admitted to the upper end of cylinder 154, driving the piston (notshown) of the motor and piston rod 158 downwardly. As is apparent fromFIG. 15, this pivots the foot assembly in a clockwise direction aboutpivot member '86 from the full line travel position to the positionshown in dotted lines. As in the case of the bed tilting mechanism, thepivotal connections between the hydraulic motor and the components towhich it is connected accommodate movement of motor 152 as the footassembly is lowered with the motor moving from the position shown infull lines in FIG. 15 to that shown in dotted lines as the foot assemblypivots through the clockwise path just described.

As mentioned previously, foot assembly 32 may be employed to stabilizevehicle 20 during loading, unloading, and other operations as well as toelevate the rear end of the vehicle from the supporting surface. Whenonly stabilization of the vehicle is involved, the flow of operatingfluid to hydraulic motor 152 is simply terminated as soon as the groundengaging shoes of the foot assembly reach ground line 166.

To return foot assembly 32 to the travel position shown in full lines inFIG. 15, the process just described is reversed by admitting operatingfluid to the lower end of hydraulic motor cylinder 154. This drives themotor piston and piston rod .158 upwardly, pivoting the foot assembly ina counterclockwise direction from a lowered to its travel position.

Referring now to FIG. 18, the system for supplying hydraulic operatingfluid to the various operating mech anisms described above includes, inaddition to control mechanism 34, a hydraulic reservoir 168 and ahydraulic pump 170; which may be driven by the power takeoff 172 ofvehicle 20. The outlet of pump 170 is connected by hydraulic lines 174and 175 to control 34 which, in the exemplary embodiment of theinvention described herein, consists of two conventional three-spool,fourway valve banks 176 and 178. These are preferably mounted on theside of sub-frame 28 near the rear of the sub-frame as shown in FIG. 1.This location permits the operator to closely observe the movement ofthe bed as he manipulates the controls. A cover (not shown) can beprovided to protect these controls from dust, rain, etc. when not inuse, if desired, inasmuch as they are in a relatively exposed location.

As shown in FIG. 18, valve bank .176 includes an operating lever 180 forconnecting hydraulic fluid line 174 to the forward and rear ends ofhydraulic motor 102 through hydraulic lines 182 and 184, respectively,to extend and retract the bed. A second operating lever 186 can bemanipulated to connect line 174 to the upper and lower ends of hydraulicmotors 124 and 126 through bydraulic lines 188-196 to tilt bed 30upwardly and to lower it to its normal, horizontal position.

As shown in FIG. 18, a check valve 198 is interposed in the hydrauliclines connected to motors 124 and 126. This is an important safetyfeature in that it prevents fluid from flowing out of the hydraulicmotors and allowing the bed to drop if there is a failure in thehydraulic system when the bed is in an elevated or tilted position.

A third operating lever 200 in valve bank 178 is provided to connecthydraulic line 174 to foot assembly operating motor 152 throughhydraulic lines 202 and 204. This permits the foot assembly to be raisedand lowered in the manner described previously.

To complete the hydraulic circuit, the hydraulic lines between themotors shown in FIG. 18 are connectable by operating levers 180, 186,and 200 to hydraulic lines 206 and 208 which, in turn, are connectedthrough a filter 210 back to hydraulic fluid reservoir 168. Theseconnections permit the operating fluid to drain from one end of a motorwhile it is being admitted to the other.

As mentioned previously, one of the significant advantages of anoperating system of the type just described is that it may readily beemployed to power not only the vehicle components described above but,also, auxiliary equipment such as winches and the like. For example, asshown in FIG. 18, the third operating lever 211 in valve bank 176 may beemployed to control the flow of hydraulic fluid to a conventional,hydraulically operated winch 212 connected to the valves controlled bylever 211 through hydraulic lines 214 and 216. The operating levers 218and 220 in valve bank 178 may be similarly utilized to regulate theoperation of other auxiliary equipment (not shown).

One of the important advantages of the present invention, as discussedabove, is the versatility resulting from the variety of positions towhich bed 30 can be manipulated. For example, FIG. 1 shows vehicle 20with bed 30 retracted and cab protector 71 and tailgate approach plate72 in their normal vertical positions. Foot assembly 32, in this figure,is in its normal or retracted position. This is one configuration whichthe vehicle could assume for travelling, either empty or loaded.

In the configuration of vehicle 20 shown in FIG. 2, bed 30 has beenpartially extended (i.e., moved rearwardly); and cab protector '71 andtailgate approach plate 72 have been lowered to increase the length ofthe bed. In one commercial application of the principles of the presentinvention, cab protector 71 is approximately four feet tall and tailgateapproach plate 72 approximately nineteen inches high so that lowering ofthese components to the horizontal position of FIG. 2 increases thelength of the bed by approximately five and one-half feet.

FIG. 3 shows vehicle 20 in a configuration for loading or unloadingmachinery, automobiles, or for loading the vehicle with a forklift orthe like. In this configuration bed 30 is tilted upwardly to its loadangle (approximately 11), and foot assembly 32 is lowered to stabilizethe vehicle. Cab protector 71 remains up but tailgate approach plate 72is lowered to permit the machinery, et cetera to be pulled onto bed 30by winch 212 or driven onto the bed. Once the vehicle is loaded, the bedis lowered and retracted and foot assembly 32 raised to the travellingposition.

For loading from a dock or the like, vehicle 20 may be positioned asshown in FIG. 4. In this type of operation, bed 30 is extended and footassembly 32 is lowered to raise the rear end of vehicle 20 oil of thesurface 222 on which it is standing until tailgate approach plate 72 islevel with the horizontal surface 224 of the dock 226. This permits theload to be moved directly from dock 226 onto vehicle bed 30. Once thisis accomplished, the bed is retracted, foot assembly 32 returned to itstravel position, and tailgate approach plate raised to ready vehicle 20for travelling.

In a number of operations, it is desirable to have the end of the bedbelow the level on which the vehicle is standing. When this is desired,the vehicle is positioned as shown in FIG. 5 with foot assembly 32lowered to raise the rear end of the vehicle above ground level 222. Bed30 is then tilted upwardly and extended until tailgate approach plate 72reaches the lower level 228.

In addition to the load angle or position shown in FIG. 3, bed 30 canalso be raised to a dump angle or position in which the surface of thebed is at an angle of up to 28 from the horizontal. The dump position isshown in FIG. 6. In this case bed 30' is kept in the retracted positionso that it may be elevated to a greater extent, and foot assembly 32 islowered to an extent sufficient to stabilize the Vehicle. As in theother configura tions, tailgate approach plate 72 is lowered.

Another type of operation in which the versatility of the presentinvention is extremely useful is in the unloading of long, heavyobjects. In the past this has typically required the use of a crane orother unloading equipment. Because of the versatility of the novelvehicle beds described herein, in contrast, such equipment is notnecessary; and objects of the type just mentioned can be readilyunloaded.

Specifically, in unloading long objects vehicle bed 30 is tiltedupwardly as described above until it reaches an angle at which theobject to be unloaded will slide down the bed by gravity. The bed isthen extended until tailgate approach plate 72 lies on the surface onwhich vehicle 20 is standing. Then, the object to be unloaded is allowedto slide down the bed onto the tailgate approach plate with thismovement being controlled by winch 212 to prevent damage to it.

With the lower end of the object being unloaded resting on the approachplate, foot assembly 32 is lowered to stabilize the vehicle and preventit from moving, and bed 30 is retracted from under the load, anoperation facilitated by the airfoil shape of the tailgate approachplate which permits it to be readily withdrawn from under the load.

In the case of a long load one end of the load will at this point beresting on the ground and the other on the truck bed. The next step isto retract foot assembly 32 and further tilt and extend bed 30 byoperation of motors 124 and 126. With the foot assembly retracted thisraises the rear end of the vehicle and permits the vehicle to rollahead. The rear end is then lowered and the bed again retracted in themanner described above, which results in the forward end of the objectbeing moved into engagement with the bed at a point closer to the rearend of the vehicle since its rear end remains stationary while thevehicle has moved forward. The cycle is repeated as many times asnecessary until the forward end of the object is lowered to the surfaceon which the vehicle is standing.

The foregoing is merely one example of how the versatility of thepresent invention may be taken advantage of in the handling of objectswhich are diflicult to load and/or unload. Other equally sophisticatedoperational sequences can of course be utilized in the handling of otherloads of this nature.

In conjunction with the foregoing it will be apparent from thedescription of the sequence of steps in the unloading operation and thedrawing that no harmful bending or other stresses are imposed on thecomponents involved during any of the steps of the operation. Anyattempt to use previously known arrangements such as those describedabove, even if it were possible (which it is not), would certainlyresult in stress loads capable of seriously damaging various ones oftheir components. In short one of the important features of the presentinvention is not only the flexibility of motion provided but, also, thearrangement of components in such a fashion that they can be manipulatedunder load to different positions such as those described above withoutbending moments or harmful stresses being imposed upon them.

As will be apparent to those skilled in the arts to which the presentinvention pertains from the foregoing description of an exemplaryembodiment, vehicles in accord with the present invention have a degreeof versatility not heretofore attainable. Such versatility can be evenfurther increased for particular applications by, for example, adding arack as suggested above, a lift, or an over-the-cab carrier to increasethe carrying capacity of the vehicle. These and other modifications ofthe illustrated embodiment of the invention are accordingly fullyintended to be covered in the appended claims to the extent that theyare not expressly excluded therefrom.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description; and allchanges which come within the meaning and range of equivalency of theclaims are therefore intended to be embraced therein.

What is claimed and desired to be secured by Letters Patent is:

1. The combination of a vehicle having a frame including a pair oflongitudinally extending frame members; a sub-frame having frame membersat opposite sides thereof; a bed carried by said sub-frame; a footassembly having side frame members connected by transverse members intoa unitary structure; means pivotally fixing said sub-frame and said footassembly to the rear of the vehicle frame, whereby the front end of thesub-frame and the bed carried thereby can be tilted upwardly away fromsaid bed; and selectively operable means for pivoting the foot assemblydownwardly relative to the vehicle frame and into engagement with thesurface on which the vehicle is standing to thereby raise and/orstabilize the rear end of the vehicle, the means for pivotally fixingsaid subframe and said foot assembly to the vehicle frame including aplatelike support member fixed to each of the longitudinally extendingvehicle frame members at the rear end thereof; upper and lower pivotmembers supported by and spanning said supports; depending members fixedto the sub-frame members and journalled on the upper pivot member,whereby said sub-frame and bed are pivotal about said upper pivotmember; and the lower 10 pivot member extending through the side membersof the foot assembly at the upper end thereof, whereby said footassembly is pivotal about the lower pivot member.

2. The combination of claim 1, wherein the foot assembly has upper andlower transverse frame members and at least one intermediate transverseframe member and wherein the selectively operable means for pivoting thefoot assembly downwardly about the lower pivot member includes afluid-operated motor having a cylinder component and a piston rodcomponent which is extensible and retractable relative to the cylindercomponent and extends through one end thereof and a bracket means fixedto the opposite end of said cylinder component, said upper pivot memberextending through said bracket means to pivotally fix said opposite endof said cylinder component to the rear end of the vehicle frame andthere being means pivotally fixing the end of the piston rod exteriorlyof the cylinder component to the intermediate transverse frame member ofthe foot assembly, whereby the connections between the vehicle frame andthe fluid-operated motor and between the fluid operated motor and thefoot assembly accommodate movement of said motor relative to the vehicleframe and the foot assembly as the foot assembly pivots relative to therear end of the vehicle frame.

3. The combination of claim 2, wherein the means pivotally fixing saidend of said piston rod component to said intermediate transverse memberof said foot assembly comprises a T-shaped fitting and a pair ofbrackets fixed in spaced relationship to said intermediate member, thearms of the fitting being journalled in the brackets to pivotally fixthe fitting thereto and the leg of said fitting being fixed to said endof said piston rod.

4. The combination of claim 1, together with a pair of ground-engagingshoes and means pivotally fixing one of said shoes to each of the sideframe members of the foot assembly at the lower end thereof.

5. The combination of claim 4, wherein each of said shoes comprises aground-engaging bearing plate and a pair of upstanding, platelikebrackets fixed to said bearing plate and embracing opposite sides of theassociated side frame member and wherein the means pivotally fixing theshoe to the side frame member comprises a pivot pin extendingtransversely through the brackets and the associated side frame member.

6. The combination of claim 1, wherein there are a pair of platelikesupport members fixed to the rear end of each of said longitudinallyextending vehicle frame members in parallel spaced apart relationship,there being upper and lower cylindrical bushing members fixed betweeneach pair of support plates, said upper pivot member extending throughthe upper bushing members and said lower pivot member extending throughthe lower bushing members.

7. The combination of claim 6, together with means fixed to said upperand lower pivot members adjacent the opposite sides of the two outermostof said pairs of platelike supports to retain said pivot members inplace, the means at at least one end of each pivot member beingdetacha'ble from the associated pivot member to accommodate the removalof the pivot member.

8. The combination of claim 6, wherein the longitudinally extendingvehicle frame members are of the channel type with the flanges thereofhorizontally oriented, said support plates being notched to fit betweenthe flanges of the structural members, whereby they can be attached tothe inner sides of both flanges of each structural member and to theexterior side of one flange thereof.

References Cited UNITED STATES PATENTS 2/1939 Helms 254-86 6/1964 Allen254-505

